It’s the moment we’ve all been waiting for — when Leonardo DiCaprio wins his first Oscar during the 88th annual Academy Awards, taking place 7:30 p.m. Sunday.

It’s a rarity to experience a sense of mystery surrounding who potential winners could be, but this year’s races are virtually wide open, fittingly coinciding with the unpredictable direction host Chris Rock could take the telecast.

But while DiCaprio’s Best Actor win for "The Revenant" is a foregone conclusion, the other major categories — Best Picture, Best Director, Best Actress, Best Supporting Actress and Best Supporting Actor — for the most part will maintain a sense of uncertainty even after the red carpet is finally laid out.

With that in mind, here are the evening’s likely winners, along with some thoughts on who should win.

Rachel McAdams, from left, as Sacha Pfeiffer, Mark Ruffalo as Michael Rezendes and Brian dArcy James as Matt Carroll, in a scene from the film, "Spotlight."(Photo: AP)

Why: While Mara is one of my favorite actresses, and Leigh’s performance has been hard to forget since her film’s Christmas Day release, Vikander had the ability to make an otherwise boring movie captivating. "The Danish Girl" has a slow pace and doesn’t offer much in terms of being entertaining or thought provoking, but every time Vikander graced the screen it provided a reason to sit up and marvel over the emotional roller coaster she was taking viewers on. Winslet is her biggest challenger having perfected a Polish accent and the Aaron Sorkin-penned dialogue, but the fact that she has already won an Oscar will take away too many votes for her to emerge the winner.

Why: The Golden Globe winner in this category has won the Oscar 90 percent of the time, so Stallone is pretty much a lock despite his emotionless delivery of generic dialogue. As good as DiCaprio’s performance in "The Revenant" was, Hardy’s was even better. So much of the investment viewers have in DiCaprio’s character’s journey to get revenge on Hardy’s character is the result of how effective Hardy is. While the other nominees’ films don’t rely on their performances, Hardy’s was a make-or-break factor for the film — and he certainly made it.

Why: The Screen Actors Guild Award winner goes on to win 70 percent of the time, so the odds are in Larson’s favor. Having already won Oscars, Lawrence and Blanchett don’t present much of a challenge and Ronan being so young hurts her chances. Not enough people saw Rampling’s film to get her enough votes. As a mother held captive, Larson had the added challenge of being confined to one setting for most of the film, as well as only being able to interact with one of two fellow actors per scene. The film is thoroughly riveting, though, and that’s a credit to the performance she gives.

Best Actor

Michael Fassbender stars as Steve Jobs in a scene from the film "Steve Jobs."(Photo: AP)

Why: Many will declare DiCaprio’s guaranteed win as the Academy rewarding his career, but truth be told it’s the best performance of the nominees. While the other four — especially Fassbender — had a plethora of dialogue to portray their character’s emotions, DiCaprio’s performance revolves around his ability to communicate his character’s anguish with facial expressions due to the vocal injuries his character suffers early in the film.

Tom Hardy as Max Rockatansky in a scene from "Mad Max:Fury Road."(Photo: AP)

Why: Only two directors have won back-to-back Best Director Oscars, but now that Inarritu has earned the Directors Guild Award — which has also been won by nine of the past 10 Best Director Oscar winners — he is virtually a lock. I’m a firm believer each year this award should go to the director whose involvement with the film elevates its quality to a place it couldn’t go with any other director, which in this case leaves Miller and Inarritu. Miller made the better movie, so he gets my vote.

Why: History would indicate "The Big Short" as the frontrunner — it took home the Producers Guild Award, which has predicted eight of the past 10 Best Picture winners. "Spotlight" also has a chance after winning the Screen Actors Guild Award, which has predicted six of the past 10 winners. However, the bigger trend is that the Oscar winner for Best Director usually predicts what will win Best Picture, and the directors of "Spotlight" and "The Big Short" don’t have a shot at winning that category. "The Revenant’s," however, does. And, with the appeal its leading actor Leonardo DiCaprio has, and the broad and epic scope of its plot, not to mention its fancy look, it’s hard to envision it not emerging the victor of the night’s most unpredictable category. The best movie this year, though, was hands down Room. Essentially two movies, its first half serves as a great depiction of how love and family can help humans persevere in the worst situations imaginable, while the second focuses on the burden society places on individuals to be normal and how it reacts to mental health and what is considered normal. It’s suspenseful, gripping and - more than any other film this year - poignant.